starship-design: Protons vs Electrons for Relativistic Electric Thrusters

[Steve VanDevender <stevev@efn.org>]

DotarSojat@aol.com writes:
 > Antimatter conversion efficiency = 1.0

That's a common misconception.  Unfortunately the annihilation products
of matter-antimatter reactions aren't all photons, and it's really damn
hard even to get the matter and antimatter to combine completely under
any realistic circumstances.  My understanding (bolstered by some
half-remembered statements by Robert Forward) is that the practical
conversion efficiency is more like 0.8.